1. Field of the Invention
This invention relates to a method of imparting a light resistance and an ultraviolet-screening action to a fibrous article.
2. Description of the Related Art
Most fibrous articles such as clothes including sports wears, beach umbrellas and curtains are exposed to sunlight in the outdoors. Therefore, the fibers of these articles deteriorate and the dyed fibrous articles discolor due to ultraviolet light. Furthermore, the skin gets sunburnt and furnishings are discolored by ultraviolet light transmitted through the fibrous articles.
To protect fibrous articles from photo-degradation and dyed fibrous articles from color fading, an ultraviolet absorber is adsorbed in the fibers. As the ultraviolet absorbers used, there can be mentioned 2-hydroxybenzophenones such as 2,4-dihydroxybenzophenone, 2,2',4,4'-tetrahydroxybenzopheneone and 2-hydroxy-4-octoxybenzophenone; and 2-hydroxyphenylbenzotriazoles such as 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2-(2'-hydroxy-3'-t-butyl-5'-methylphenyl)-5-chlorobenzotriazole and 2-(2'-hydroxy-3',5'-dibutylphenyl)-5-chlorobenzotriazole.
Most known conventional ultraviolet absorbers have a low-molecular-weight and the adsorbed ultraviolet absorbers are dissolved in a laundering bath. Therefore, the ultraviolet screening action does not last over a long period of time.